On our last visit we stayed in one of the family suites at the All Star Music. It has two bathrooms, a mini kitchen with a coffee maker, microwave, mini frig, & sink, a bedroom, and a living room. We had 4 adults and 3 kids in the family suite. We also had two additional people in another regular room. From the size of your party you may need 2 suites and a regular room?? or 3 suites???
If you are flying to Disney, a bonus for staying on property is not having to rent vehicles as you can use the Disney buses.
I am note sure how the prices of the family suites compare to renting a condo or house but it may be something to check into.
Just be sure to research and weigh all your options: pros and cons.